Fluid ejectors are known. For example, in U.S. Pat. No. 6,318,841 to Charles P. Coleman et al., there is disclosed in FIGS. 1-3 a plurality of fluid ejectors 100, 200, 300 arranged to eject at least one fluid. The fluid may comprise, for example, marking fluid or ink. In other embodiments, the fluid may comprise any of biological fluids, medical fluids or chemical fluids.
It is known to use fluid ejectors to mark a media. For example, in the foregoing Charles P. Coleman et al. patent there is disclosed in FIGS. 12-13 a plurality of image forming devices 1200, 1300 arranged to eject at least one marking fluid on a media thus forming an image on the media. In one embodiment, the marking fluid is ink.
Other examples of fluid ejectors are discussed below.
In U.S. Pat. No. 5,555,461 to John C. Ackerman, in FIG. 1 there is depicted a printhead 12 arranged to eject ink that is supplied by ink supply 14.
In U.S. Pat. No. 5,943,071 to Karai P. Premnath there is depicted in FIG. 1 a color ink jet printer 10 comprising a color printhead 18 having a plurality of recording segments 18A, 18B, 18C and 18D each respectively connected to ink containers 20, 22, 24 and 26.
In U.S. Pat. No. 6,213,582 to Haruo Uchida et al. there is depicted in FIG. 3 an ink jet recording head 21 comprising ink jet ports 21a arranged for discharging ink droplets on a media.
It is also known to attach a radio frequency (“RF”) tag to an article, the tag including stored data pertaining to the article, and to arrange a remote RF station to retrieve the stored data by RF transmission from the RF tag. For example, in U.S. Pat. No. 6,346,884 to Gakuji Uozumi et al. there is depicted in FIG. 1 an RF tag 12 attached to an article 11, the tag 12 including a memory 14f for disposing data about the article 11, the tag 12 arranged to RF transmit the stored data to a remote RF apparatus 10.
It is known for an image forming device to form an image on a media based on an input image information. One example of such an image forming device is the well-known ink jet printer that forms an image on a media by means of at least one included ink jet ejector device or printhead.
In a color imaging device, for example, the input image information comprises red (“R”), green (“G”) and blue (“B”) color components. The color imaging device uses one or more color look-up tables to convert, translate or transform the input RGB image information into marking fluid information. The marking fluid information, in turn, is used to control the ejection of a plurality of separate marking fluid colorants on a media to thereby form an output image on the media. Typically, the color imaging device will use four (4) individual marking colorants comprising cyan (“C”), magenta (“M”), yellow (“Y”) and black (“K”). As a result, the color imaging device will use suitable color look-up tables to convert the RGB input image information to the desired output C, M, Y and K (collectively known as “CMYK”) marking fluid information. Some examples of such RGB input-to-CMYK output color look-up tables are found in the following U.S. patents to Robert J. Rolleston et al.: “Color printer calibration architecture,” U.S. Pat. No. 5,305,119; “Color printer calibration with blended look up tables,” U.S. Pat. No. 5,483,360; and “Color printer calibration architecture,” U.S. Pat. No. 5,528,386.
Image-rendering procedures, particularly the generation of color look-up tables, must be matched to the expected performance of the printheads in an ink jet printer. For example, the color look-up tables that are developed to produce the desired color rendition are often generated using a good quality ink ejector with “nominal” drop volumes for each color. In practice, however, printheads coming off the manufacturing line will produce drop size volumes that vary from printhead to printhead. If these variations are large, the resulting output from a particular printhead will appear “light” or “dark” depending on whether the ejected drops from that printhead are smaller or larger than “nominal”, respectively. Thus, users may perceive differences in color rendition, print quality, or both, from printer to printer or when printheads are replaced within a printer. These rendering differences may be unacceptable for some users and some applications. For photo images on glossy media, for example, tests show that images made with 10-12 pico-liter (“pl”) drops will be reasonably lighter than images produced with 12-14 pl drops.
One method of minimizing perceived variations in output due to these effects is to improve processing techniques, tighten manufacturing tolerances, or both. The goal is to produce all printheads so that their ink drop ejection characteristics, namely, drop volume or drop size, are very nearly identical so that there is no perceived difference in output produced by different printheads. Unfortunately, this approach has a disadvantage of increasing the unit manufacturing cost and lowering the yield.
Another method of minimizing perceived variations in the output from printhead to printhead is to have the user make use of special software tools such as photo editing, contrast or brightness knobs or settings inside the printer driver. These methods have the disadvantage of requiring user intervention, special software, and possibly knowledge of the printer driver, which many customers never use to change settings from default.